Sewage treatment device

Abstract

The invention relates to the technical field of sewage treatment, and discloses a sewage treatment device to solve the problem of calcium ion pollution in an anaerobic biological treatment process in the prior art. The sewage treatment device comprises an anaerobic reaction cavity, a vortex screener and a cation exchanger are arranged in the anaerobic reaction cavity, and the vortex screener is arranged in the cation exchanger. According to the technical scheme, the high-flow-speed water-gas mixed liquid serves as a power source of the vortex screener, and the operation cost is saved. The vortex screener is used for screening calcified anaerobic particles and normal anaerobic granular sludge by utilizing centrifugal force, so that accurate discharge of the calcium anaerobic granular sludge is realized. The cation exchange resin filled in the cation exchanger has an extremely strong adsorption effect and can selectively adsorb calcium ions in liquid, and particularly, the calcium ions in sewage are effectively removed by utilizing high-speed rotating water-gas mixed liquid, so that the concentration of the calcium ions is greatly reduced, the calcification process of granular sludge is greatly relieved, and pipeline scaling is effectively prevented.

Description

Technical Field

[0001] The present application relates to the technical field of sewage treatment, in particular to anaerobic biological sewage treatment technology, and specifically to a sewage treatment device. Background Art

[0002] Wastewater treatment focuses on high efficiency, energy saving, integration and diversification. Anaerobic biological treatment technology is considered to be a low-carbon treatment technology that removes pollutants from sewage and recovers energy.

[0003] Anaerobic biological treatment uses anaerobic microorganisms to synergistically degrade organic pollutants in wastewater and convert them into biogas to achieve sewage purification. It has the advantages of high treatment load, low operating cost and energy recovery. Therefore, anaerobic biological treatment technology is widely used in the field of high-concentration organic wastewater treatment, such as beer wastewater, papermaking wastewater and food processing wastewater. At present, a large number of high-efficiency anaerobic granular sludge bed reactors with anaerobic granular sludge as the core play an important role in sewage treatment, such as upflow anaerobic sludge blanket Upflow anaerobic sludge blanket, UASB, expanded anaerobic granular sludge bed, EGSB, internal circulation anaerobic reactor Internal circulation, IC, etc.

[0004] According to an anaerobic bioreactor disclosed in Chinese patent CN114394665A, the basic structure of the anaerobic bioreactor includes a corrosion-resistant reaction chamber, in which an anaerobic sludge bed is arranged. The early upflow anaerobic sludge bed was developed by Professor Lettinga of the Netherlands in the 1970s as a high-efficiency anaerobic bioreactor. The reactor consists of a cylindrical reaction chamber, with a water inlet pipe and a water distributor installed at the bottom. The anaerobic sludge bed is arranged above the water distributor. When the reactor is working, the wastewater enters the bottom of the reactor through uniform water distribution, and undergoes biodegradation reaction from bottom to top through the anaerobic sludge bed. Finally, the solid waste is removed through a three-phase separator, and biogas and liquid are collected.

[0005] High-efficiency anaerobic granular sludge bed reactor has the advantages of high treatment load, low operating cost and energy recovery, and is widely used in high-concentration industrial wastewater treatment. However, when used to treat high-concentration calcium-containing industrial wastewater, such as papermaking wastewater, leather wastewater and soybean wastewater, high-concentration calcium ions Ca 2+ The deposition of calcium carbonate (CaCO3) and calcium phosphate (Ca5(PO4)3(OH)) on the surface and inside of the granular sludge increases the inorganic components in the anaerobic granular sludge, which reduces the permeability of the granular sludge, causing the functional microorganisms to be in a state of starvation or even death, thereby reducing the wastewater treatment effect.

[0006] In order to remove the calcified anaerobic granular sludge in the granular sludge, people began to install a vortex screener in the anaerobic reaction chamber (see Chinese patent CN208577615U), using the centrifugal force generated by the high-speed rotating water vapor flow to remove the anaerobic granular sludge contaminated by calcium ions. However, although this screening and decalcification device can remove part of the anaerobic granular sludge contaminated by calcium ions, it cannot effectively remove the calcium ions in the liquid. Summary of the invention

[0007] The main purpose of the present application is to provide a sewage treatment device to solve the problem of calcium ion pollution in the anaerobic biological treatment process in the prior art.

[0008] In order to achieve the above-mentioned purpose, according to one aspect of a specific embodiment of the present application, a sewage treatment device is provided, including an anaerobic reaction chamber, wherein the anaerobic reaction chamber has a built-in vortex screen, and is characterized in that it also includes a cation exchanger, wherein the vortex screen is placed in the cation exchanger.

[0009] In some embodiments, the anaerobic reaction chamber is cylindrical; the vortex screener and the cation exchanger are both composed of cylinders made of mesh material, and the cation exchanger and the vortex screener are coaxial with the anaerobic reaction chamber; the cation exchanger is mounted outside the vortex screener, and cation exchange resin is filled therein.

[0010] In some embodiments, the lower end of the cylinder is contracted into a frustum.

[0011] In some embodiments, the cone taper is 20-30°.

[0012] In some embodiments, a mud inlet pipe is installed on the vortex screener, one end of the mud inlet pipe extends into the vortex screener, and the other end is placed outside the cation exchanger and is provided with a mud inlet.

[0013] In some embodiments, the mud inlet pipe and the mud inlet port have rectangular cross-sections.

[0014] In some embodiments, the mud inlet pipes are evenly distributed along the radial direction of the screener.

[0015] In some embodiments, the axial angle between the mud inlet pipe and the screener is an acute angle.

[0016] In some embodiments, the anaerobic reaction chamber has a height-to-diameter ratio of (2-10):1

[0017] In some embodiments, the diameter ratio of the cation exchanger to the sifter is (1.5-3):1.

[0018] According to the technical solution of the present application and the further improved technical solution in certain exemplary embodiments thereof, the present application has the following beneficial effects:

[0019] The sewage treatment device of the present application, its anaerobic reactor includes five functional areas: mud collection area, water distribution area, cyclone screening area, three-phase separation area and gas-liquid reflux area. It has a compact structure and small footprint. The high-flow rate water-gas mixture is used as the power source of the vortex screener to save operating costs. The vortex screener uses centrifugal force to screen calcified and normal anaerobic granular sludge. The calcified anaerobic granular sludge with a larger specific gravity is subjected to a larger centrifugal force, while the normal granular sludge with a smaller specific gravity is subjected to a smaller centrifugal force, forming a heavy bottom and light top distribution in the reactor, and realizing the precise discharge of calcium anaerobic granular sludge. The cation exchange resin filled in the cation exchanger has a very strong adsorption effect, selectively adsorbs calcium ions in the liquid, effectively removes calcium ions in the sewage, greatly reduces the calcium ion concentration, and is very helpful in alleviating the calcification process of the granular sludge and preventing pipe scaling.

[0020] The present application is further described below in conjunction with the accompanying drawings and specific embodiments. Additional aspects and advantages of the present application will be partially given in the following description, partially become apparent from the following description, or be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings constituting a part of this application are used to provide a further understanding of this application. The specific implementation modes, illustrative embodiments and their descriptions of this application are used to explain this application and do not constitute an improper limitation on this application. In the drawings:

[0022] Figure 1 It is a schematic diagram of the structure of a sewage treatment device according to a specific implementation method of the present application;

[0023] Figure 2 is a schematic structural diagram of a cation exchanger according to a specific embodiment;

[0024] Figure 3 It is a schematic diagram of the configuration relationship and structure of a vortex screener and a cation exchanger in a sewage treatment device according to a specific implementation method.

[0025] In the figure: mud collecting area I, water distribution area II, cyclone screening area III, three-phase separation IV, gas-liquid reflux area V, water distributor 1, cation exchange resin outlet 2, mud inlet pipe 3, mud inlet 30, vortex screen 4, overflow pipe 5, cation exchanger 6, overflow conduit 7, guide 8, cation exchange resin inlet 9, three-phase separator 10, water outlet weir 11, exhaust pipe 12, one-way valve 13, purifier 14, ejector 15, sludge hopper 16, mud discharge pipe 17, reflux pump 18, liquid reflux pipe 19, gas reflux pipe 20, gas-liquid mixing pipe 21, sludge settling port 22, water storage chamber 23, nozzle 24. DETAILED DESCRIPTION

[0026] It should be noted that, in the absence of conflict, the specific implementation modes, exemplary embodiments and features thereof in this application can be combined with each other. The present application will now be described in detail with reference to the accompanying drawings and in combination with the following content.

[0027] In order to enable those skilled in the art to better understand the solution of this application, the following will be combined with the drawings in the specific implementation methods and exemplary embodiments of this application to clearly and completely describe the technical solutions in the specific implementation methods and exemplary embodiments of this application. Obviously, the described exemplary embodiments are only part of the embodiments of this application, not all of them. Based on the specific implementation methods and exemplary embodiments in this application, all other implementation methods and embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of this application.

[0028] The sewage treatment device of the present application installs a cation exchanger in the original anaerobic reactor, places a vortex screen in the cation exchanger, and uses the high-speed rotating water flow of the vortex screen to increase the contact opportunity between the cation exchange resin and the calcium ions in the sewage, improve the cation exchange rate, effectively remove the calcium ions in the sewage, and greatly reduce the calcium ion concentration, which is very helpful to alleviate the calcification process of the granular sludge and prevent the scaling of the pipeline. In conjunction with the vortex screen to remove the contaminated anaerobic granular sludge, the sewage treatment device of the present application can effectively improve the sewage treatment efficiency of the anaerobic reactor.

[0029] Example

[0030] like Figure 1 , 2As shown, the sewage treatment device of the present application is respectively composed of mud collection area I, water distribution area II, cyclone screening area III and three-phase separation area IV from bottom to top, and the left part of the reactor is gas-liquid reflux area V. A sludge hopper 16 is provided at the bottom of the mud collection area I, and the sludge hopper 16 is connected to the mud discharge pipe 17. A water distributor 1 is provided in the water distribution area II, and the pipe mouth of the water distributor 1 is downward. The cyclone screening area III is divided into an external biological reaction area and a central cyclone area. The external biological reaction area is filled with anaerobic granular sludge, and the central cyclone area is provided with a vortex screener 4. The vortex screener 4 is connected to the mud inlet pipe 3 and the overflow conduit 7. The vortex screener 4 is provided with an overflow pipe 5 inside and a guide 8 is provided on the upper part. The resin inlet 9 is above the guide 8, and the lower part of the vortex screener 4 is connected to the mud settling port 22. The cation exchanger 6 is set outside the vortex screener 4, and the cation exchange resin is filled therein. The cation exchanger 6 connects the cation exchange resin outlet 2 and the cation exchange resin inlet 9. The three-phase separation zone IV is provided with a three-phase separator 10, a water outlet weir 11, and an exhaust pipe 12. The gas-liquid reflux zone V is provided with an ejector 15, a liquid reflux pipe 19, a gas reflux pipe 20, and a gas-liquid mixing pipe 21. The ejector 15 includes a water storage chamber 23 and a nozzle 24. The high-speed gas-liquid mixed fluid generated by the ejector 15 enters the vortex screener 4 through the gas-liquid mixing pipe 21, and forms a high-speed rotating gas-liquid mixed fluid in the vortex screener 4. The liquid reflux pipe 19 is connected to the reflux pump 18, and the gas reflux pipe 20 is connected to the purifier 14 through the one-way valve 13.

[0031] In the sewage treatment device of this example, the anaerobic reaction chamber adopts a conventional cylindrical structure with a height-to-diameter ratio of (2-10):1, and the volume ratio of the sludge collection zone I, the water distribution zone II, the sludge bed zone III, the cyclone screening zone III and the three-phase separation zone IV is 3:1:(11-13):(7-9).

[0032] In this example, the vortex screen 4 and the cation exchanger 6 are both composed of cylinders made of mesh material. Figure 2 The front view of the cation exchanger is shown. The shape of the vortex screener 4 is the same as that of the cation exchanger 6, and the size is smaller than that of the cation exchanger 6. The diameter ratio of the cation exchanger 6 and the vortex screener 4 is (1.5-3):1. The mesh aperture of the mesh material should be smaller than the particle size of the granular sludge and the cation exchange resin to prevent the resin from mixing and contaminating the granular sludge. The cation exchanger 6 and the vortex screener 4 are coaxially installed with the anaerobic reaction chamber. The cation exchanger 6 is mounted outside the vortex screener 4, and the gap between the cation exchanger 6 and the vortex screener 4 is filled with cation exchange resin.

[0033] In this example, the vortex screener 4 and the cation exchanger 6 are composed of a cylinder and a truncated cone. The upper and lower bottom surfaces of the cylinder have the same diameter, and the height-diameter ratio is (2-3):1. The height of the truncated cone is about 800 mm, and the ratio of the upper bottom diameter to the lower bottom diameter is about 3:1. The taper is 20-30°. The truncated cone of the vortex screener 4 and the cation exchanger 6 can be formed by gradually shrinking the cylinder.

[0034] In this example, a mud inlet pipe 3 is installed on the vortex screener 4. The mud inlet pipe 3 is evenly distributed along the radial direction of the vortex screener 4, and the angle between the mud inlet pipe 3 and the axial direction of the vortex screener 4 is an acute angle (less than 90°), which is conducive to the flow of anaerobic granular sludge. One end of the mud inlet pipe 3 extends into the vortex screener, and the other end is placed outside the cation exchanger. The mud inlet pipe 3, the part outside the cation exchanger is arranged with a mud inlet 30. The mud inlet pipe 3 is a rectangular tube, and its cross-section shape is rectangular. The mud inlet 30 is also a rectangular structure, such as Figure 3 shown.

[0035] In this example, the overflow pipe 5 has a height-to-diameter ratio of (8-10):1, and the deflector 8 installed on the top of the vortex screener 4 is a right cone with a height-to-diameter ratio of 1:(1-2), and the angle between the cone generatrix and the bottom is about 60°. The overflow conduit 7 is installed at the upper end of the vortex screener 4, and passes through the cation exchanger to communicate with the anaerobic reaction chamber. The diameter of the overflow conduit 7 is about 20-50 mm. The cation exchange resin inlet 9 has the same diameter as the cation exchange resin outlet 2, and the ratio of the cation exchange resin inlet 9 to the overflow conduit 7 is (2-5):1. The water storage chamber 23 in the ejector 15 of this example is funnel-shaped, with a ratio of the upper bottom diameter to the lower bottom diameter of (10-15):1, and a height of about 500-600 mm.

[0036] The working process of this sewage treatment device is as follows:

[0037] The wastewater flows through the water distribution area 1, the sludge collection area Ⅰ, the water distribution area Ⅱ and enters the biological reaction area in the cyclone screening area Ⅲ. The wastewater in the biological reaction area contacts the filled anaerobic granular sludge in the biological reaction area and undergoes anaerobic reaction. The dissolved pollutants in the wastewater are absorbed and metabolized by microorganisms and converted into biogas bubbles, thereby obtaining a three-phase mixture containing biogas, and achieving the removal of organic matter in the wastewater. The bubbles attach to the anaerobic granular sludge and carry the granular sludge up to the three-phase separation area Ⅳ. A part of the liquid in the three-phase mixture is discharged from the outlet weir 11, and a part of the liquid enters the ejector 15 through the liquid return pipe 19 under the action of the reflux pump 18. When the water flows through the nozzle 24 of the ejector 15, the flow rate increases and the pressure decreases, sucking in the biogas generated by the anaerobic granular sludge in the anaerobic bioreactor, and the generated biogas passes through the gas return pipe 20 and the purifier 14 and mixes with the return wastewater, and enters the vortex screener 4 at high speed through the gas-liquid mixing pipe 21 to form a high-speed rotating fluid. In the central cyclone zone in the cyclone screening zone III, when the wastewater flows through the cation exchanger 6 filled with cation exchange resin, the calcium ions in the wastewater react with the exchange ions of the active groups of the resin, thereby being removed. The anaerobic granular sludge in the anaerobic granular sludge bed enters the vortex screener 4 through the mud inlet 30 along the mud inlet pipe 3, and forms a rotating column in the cylinder of the vortex screener 4, generating a strong centrifugal force. The calcified anaerobic granular sludge is subjected to a greater centrifugal force due to the increase in specific gravity, and the sedimentation speed in the centrifugal field increases. The density difference with the sedimentation medium is also greater, resulting in a greater sedimentation acceleration of the calcified anaerobic granular sludge. Therefore, the calcified anaerobic granular sludge is thrown toward the cylinder wall under the action of centrifugal force, gradually flows downward to the mud collection zone I, and is discharged from the mud discharge pipe 17, while the normal anaerobic granular sludge with a small specific gravity is subjected to a smaller centrifugal force, moves upward along the overflow pipe 5, and returns to the sludge bed through the overflow conduit 7.

[0038] The technical solution of the present application is that the key to the decalcification process of calcium ions in liquid lies in the design of the vortex screener mud inlet pipe and the cation exchanger. When entering the vortex screener, the anaerobic granular sludge is prone to impact with the wall of the device to produce local vortices. The local vortices cause the movement of the fluid to become complicated, making the movement of the anaerobic granular sludge in the vortex screener disordered. This disordered movement will interfere with the normal sedimentation and separation process of the anaerobic granular sludge. In addition, local vortices may cause the separated anaerobic granular sludge to be remixed, causing the calcified anaerobic granular sludge to enter the overflow, while the normal anaerobic granular sludge enters the underflow, reducing the separation efficiency. The cross-sectional area of ​​the vortex screener mud inlet pipe is designed to be rectangular. When the fluid enters the vortex screener in a tangential direction, the rectangular cross-section helps to maintain the laminar state of the fluid, forming a more uniform vortex, and reducing the local vortices caused by the impact of the anaerobic granular sludge with the wall when entering the vortex screener. The cation exchanger is mounted on the outside of the vortex screener and is made of mesh material, which can achieve effective contact between wastewater and cation exchange resin and improve ion exchange efficiency. The mesh aperture should be smaller than the granular sludge and resin particle size to prevent mixed contamination of resin and granular sludge.

Claims

1. A sewage treatment device, comprising an anaerobic reaction chamber, wherein the anaerobic reaction chamber has a built-in vortex screen, characterized in that: The invention also comprises a cation exchanger, wherein the vortex screener is placed in the cation exchanger.

2. A sewage treatment device according to claim 1, characterized in that: The anaerobic reaction chamber is cylindrical; the vortex screener and the cation exchanger are both composed of cylinders made of mesh materials, and the cation exchanger and the vortex screener are coaxial with the anaerobic reaction chamber; the cation exchanger is sleeved outside the vortex screener, and cation exchange resin is filled therein.

3. A sewage treatment device according to claim 2, characterized in that: The lower end of the cylinder is contracted into a frustum.

4. A sewage treatment device according to claim 3, characterized in that: The cone taper is 20-30°.

5. A sewage treatment device according to claim 2, characterized in that: The vortex screener is provided with a mud inlet pipe, one end of which extends into the vortex screener, and the other end of which is placed outside the cation exchanger and is provided with a mud inlet.

6. A sewage treatment device according to claim 5, characterized in that: The cross sections of the mud inlet pipe and the mud inlet are rectangular.

7. A sewage treatment device according to claim 5, characterized in that: The mud inlet pipes are evenly distributed along the radial direction of the screener.

8. A sewage treatment device according to claim 5, characterized in that: The axial angle between the mud inlet pipe and the screener is an acute angle.

9. A sewage treatment device according to claim 2, characterized in that: The height-to-diameter ratio of the anaerobic reaction chamber is (2-10):

1.

10. A sewage treatment device according to claim 9, characterized in that: The diameter ratio of the cation exchanger to the sifter is (1.5-3):1.

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